Clustered PolicyCenter servers

During the start of the first server node in the PolicyCenter cluster, PolicyCenter creates a digest of all the configuration files and their parameters that are present on the start-up node. PolicyCenter then stores this configuration information in the database. This information becomes the official configuration information for the entire cluster.

In the usual course of events, as each subsequent PolicyCenter node starts, PolicyCenter performs a configuration verification for that node. If there is a difference between the configuration for that node and the configuration information stored in the database, PolicyCenter decides how to handle the difference in the two configurations:
  • If the new configuration is non-compatible with the existing cluster configuration, PolicyCenter requires a full database upgrade.
  • If the difference between the two configuration is within defined parameters, PolicyCenter requires a rolling upgrade only.

It is possible to have two seemingly identical configuration files that differ in their effect by including or excluding parts of each configuration through the use of env or serverid settings. PolicyCenter creates different digests from these configuration files. Be aware that PolicyCenter considers these digests to be different from each other and potentially non-compatible.